Distal Gastric Bypass

"Dr. Hess gave a talk on his specialized approach to obesity surgery, which coincidentally was inspired by Dr. DeMeester's duodenal switch procedure that he had developed for patients with bile reflux gastritis," says Dr. Anthone. "Dr. Hess's approach made so much sense to me that I introduced myself, and told him about my connection to Dr. DeMeester," whom he had never met. Dr. Hess, who had been performing the distal gastric bypass with the duodenal switch operation since 1987, invited Dr. Anthone to Bowling Green, and in three subsequent trips, Dr. Anthone assisted in about 20 surgeries. "The experience was like a mini obesity surgery fellowship in the sense that there is no formal obesity surgery training in any surgery residency program," he says. "Most of these operations are performed in the private setting."

Dr. Anthone notes that the distal gastric bypass with the duodenal switch helps morbidly obese patients lose weight because it combines moderate food restriction with the malabsorption of fats. "Fats cannot be absorbed into the body unless they become water soluble, which is accomplished by bile. This operation is based on the ability to keep bile from mixing with the food," he says.

The operation first involves removing the greater curvature of the stomach, reducing stomach volume to 100 to 150 ccs in size (compared to 20-30ccs in the other obesity operations).

This moderate restriction is done to limit food intake as well as to reduce excess stomach acid, and thus prevent ulcer formation. The remaining stomach, however, still allows patients to eat a fairly normal sized meal as it gradually enlarges over the period of 1-2 years. Next, the small intestine is divided at about its midpoint. The end of the "distal" small bowel is attached to the duodenum just past the stomach and the other end is attached to the intestine approximately 100 centimeters (3 to 4 feet) from its junction with the large bowel. This creates one tract for food an another for transporting bile and pancreatic juices down to the food. Full digestion and absorption of fat begins where the tracts meet.

"We divide the intestine so that about 50 percent of it contains the bile and pancreatic enzymes, and 50 percent contains food from the stomach. The two mix in only the last 15 to 20 percent of the small intestine, allowing just a small percentage of the fats to be digested," he says. "There is no 'dumping syndrome' because the food has traveled through he stomach."

This key aspect of the operation, that the pyloric valve of the stomach is left intact, facilitates a controlled release of stomach contents into the intestine - thus further avoiding the "dumping syndrome." Also in every operation, Dr. Anthone removes the gallbladder and, at times, the appendix. The gallbladder is taken out because of the higher risk of future gallstone formation after this procedure. "The appendix is removed if there is any visible abnormality seen at the time of surgery," Dr. Anthone explains.

One piece of equipment that makes this surgery possible is a special retractor that allows the surgeon to obtain good exposure in-patients whose abdomens are extremely thick (see photo). The retractor is actually bolted to the surgery table using four posts. Large, deep blades can then be inserted to get the necessary exposure.

"It must be kept in mind that this is major abdominal surgery on patients who are already at higher risk for both operative and post-operative complications," says Dr. Anthone. "We do everything we can to try to help patients get through and recover from their surgery, but the patient should be aware that risks and complications are always possible."